docs: Align soft_wrap reference with naming pattern used (#20080)

Release Notes:

- N/A

assets/settings/default.json

@@ -152,7 +152,7 @@
   "show_signature_help_after_edits": true,
   // Whether to show wrap guides (vertical rulers) in the editor.
   // Setting this to true will show a guide at the 'preferred_line_length' value
-  // if softwrap is set to 'preferred_line_length', and will show any
+  // if 'soft_wrap' is set to 'preferred_line_length', and will show any
   // additional guides as specified by the 'wrap_guides' setting.
   "show_wrap_guides": true,
   // Character counts at which to show wrap guides in the editor.